Opuntia ficus indica fruit gum: Extraction, characterization, antioxidant activity and functional properties.

A high molecular weight biopolymer was extracted from the fruits Opuntia ficus indica and characterized regarding physicochemical and rheological properties. Total carbohydrate, ash and moisture content of the polysaccharide extracted from the fruits of Opuntia ficus indica (OFIFG) were 88.85 ± 5.2%, 9.00 ± 1.30%, and 7.65 ± 0.74%, respectively. OFIFG had glucose (78.0%), arabinose (12.9%), xylose (4.8%), galactose (2.4%), and mannose (2.4%), suggesting an arabinoglucan structure. Weight average molecular weight of OFIFG was to be 3.67 × 106 g/mol. The intrinsic viscosity of OFIFG was 0.37 dL/g in deionized water at 25 °C. Steady shear measurement demonstrated that OFIFG is a shear thinning fluid. At low frequency, the gum solution exhibited a concentrated behavior. The anti-DPPH radicals activity of the gum sample was comparable to that of BHT and more than the data cited for other natural polymers. It can be found that OFIFG can be used as thickener, stabilizer and antioxidant agent in food and pharmaceutical systems.